Solid compressed amino acid spermicidal vehicle



United States Patent SOLID COMPRESSED AMINO ACID SPERMICIDAL VEHICLE William C. Mende, Neshanic, and John L. Seidel, North Plainfield, N.J., assignors to Ortho Pharmaceutical Corporation, a corporation of New Jersey No Drawing. Application July 30, 1956 Serial No. 600,666

17 Claims. (Cl. 167--58) This invention relates to pharmaceutical vehicles which disintegrate rapidly when introduced intravaginal ly, and is a continuation-in-part of our application Serial No. 524,262, filed July 25, 1955, now abandoned. More particularly, this invention relates to dry, solid, pharmaceutical vehicles, such as tablets, pellets, and the like, which disintegrate within a short period of time after insertion intravaginally to promptly release a therapeutic, medicinal, or other pharmacologically active material incorporated therein.

Solid or semi-solid pharmaceutical vehicles which dissolve or disintegrate under the influence of body heat and fluids have been formulated heretofore. Generally, these vehicles have been formulated to dissolve or disintegrate over extended periods of time so that the ingredient incorporated therein will be released slowly to exercise its properties by degrees to give a prolonged effect. Glycerin and gelatin suppositories are well-known examples or semi-solid vehicles of this type and usually require exposure of about thirty minutes or more at body temperatures to melt. Other such vehicles have been formulated to dissolve or disintegrate over longer periods of time.

For certain purposes, however, it is especially desirable to provide a pharmaceutical vehicle in dry, solid, compressed form which will disintegrate rapidly after in- 'troduction intravaginally so that the ingredient incorporated in the vehicle will be released quickly to exercise its function shortly after introduction. Vehicles of this type have particular application in the field of contraception and for certain therapeutic treatments where it is necessary to obtain prompt application of the ingredient incorporated in the vehicle to the desired body area.

Earlier attempts to provide such vehicles usually employed various agents, such as a combination of an acid 'and sodium bicarbonate, which would effervesce or foam upon contact with body fluids to effect disintegration of the vehicle. The rate of disintegration of these vehicles was too slow principally because of the formation of a film or blanket on the exterior of the vehicle which retarded penetration of vaginal fluids into the interior of the vehicle to effect complete and rapid disintegration. For example, a combination of sodium bicarbonate and an acid did not produce effective, rapid disintegration because the carbon dioxide foam which was formed blanketed the exterior surface of the vehicle and acted as a barrier between body fluids and the interior of the vehicle. In addition, vehicles of this type were unsatisfactory because they had poor storage properties and often broke when shipped.

We have discovered that a dry, solid, compressed pharmaceutical vehicle which disintegrates rapidly when in troduced intravaginally may be obtained by providing a vehicle of urea, a wicking agent as defined below, and a compound present in sufficient quantities to be nontoxic and nonirritating and to provide the vehicle with an acid -'pH; By rapid disintegration, we refer to disintegration within a period of about five minutes after the vehicle is 2 introduced intravaginally, and contacts about one cubic centimeter of vaginal fluid.

The vehicle of our invention has numerous applications where it is necessary and desirable to provide prompt and effective application of an incorporated ingredient or compound intravaginally. Within a short time after introduction intravaginally, the vehicle of our invention disintegrates and promptly releases the ingredient incorporated therein. While not limited thereto, the vehicle of our invention is particularly suitable as a carrier for spermicidal agents.

Because it is very soluble in water, urea alone, in dry, compressed form, would appear to be suitable as a vehicle which would disintegrate rapidly when introduced intravaginally. However, tests conducted on such vehicles made of urea alone revealed that rapid disintegration did not occur. The urea merely dissolved slowly over an extended period of time. Dissolution of the urea occurred on the surface of the vehicle in direct contact with vaginal fluid and proceeded inwardly towards the interior as the urea on the surface dissolved. It was then considered that more rapid disintegration would be obtained by combining'with urea a material which would conduct the vaginal fluid by physical or other means into the interior of the vehicle. For example, it was considered that by combining certain fibers, such as cellulos-ic fibers, with urea, the vaginal fluid. at the surface of the vehicle would be absorbed by the fibers and conducted into the interior of the vehicle by capillary action or some similar action. When clinical tests were conducted on such vehicles, it was found that, during certain stages in the female ovulatory cycle, gelatinization of vaginal fluid occurred. This was apparently brought about by coaction between the urea and vaginal fluid. Gelatinization of the fluid occurred before and after the time of ovulation and resulted in the formation of a film on the exterior of the vehicle which acted as a barrier to penetration of vaginal fluid into the interior. Therefore, during these stages in the ovulatory cycle, a vehicle of this type would be unacceptable as a rapidly disintegrating vehicle, particularly for contraceptive purposes. Whereupon, We then discovered that by incorporating a substance which would impart acidity to the vehicle, rapid disintegration could be obtained.

The vehicle of our invention comprises, in general, a dry, solid amino acid or a mixture of amino acids in compressed form, with about 1 percent to about 30 percent of a wicking agent which conducts vaginal fluid into the interior of the vehicle. In addition to the amino acid or mixture of amino acids, another compound may be present in suflicient quantities to be nontoxic and nonirritating under conditions of use and to provide the vehicle with an acid pH, preferably from about 3.5 to about 6.5. The amino acids may, of course, be present in the form of their salts.

Our invention may be more fully understood by con-. sidering the following examples which are for illustrative purposes only. The may obviously be modified Without departing from our invention and we, therefore, do not intend to limit our invention to the specific embodiments set forth. All parts are given by weight.

Example III Pyruvic acid 0.5 Wool, 200-325 mesh 0.5 Ar-ginine hydrochloride 99.0 Example IV Glycolic acid I H 2.5 Silk, 40-100 mesh. 20.0 Serine 77.5

Example V r a: .x- 5.0 Cotton, 100-200-mesh 8.0 Cysteine hydrochloride 87.0

Example VI Boricacid 5.0 Silk,- 200-325 mesh 6.0 Cystinehydrochloride 89.0

Example VII Urea hydrochloride 7.0 Rayon, 40-100 mesh 4.0 Lysine hydrochloride 89.0 Example-VIII Glycerophosphoric acid, 25% 1.5 Aluminum carboxymethyl cellulose, 100-200 mesh Ya ine. ydro h r d ----:-.o H. 9.3- Example IX Citric acidi 1.0 Oxycellulose, 200-325 mesh 3.0 flrAlan no 96.0

Example X Ascorbic acid -0 carboxymethyl cellulose acid, 100-200 mesh 2.0 Proline hydrochloride 97.0

Example XI Phenylacetic acid 1 .0 Wool, 40-100 mesh 7.0 Leucine hydrochloride 9 2.0

Example XII Glutamic acid 1.0 Calcium alginate, 100-200 mesh 15.0 Glycine 84.0

ExampleXIII Sorbic acid 2.0 Cotton, 200-325 mesh 12.0 Tyrosine hydrochloride 86.0

Example XIV Adipic acid I 2.5 Carboxymethyl cellulose acid, 100-200 mesh 1.5 Phenyl alanine hydrochloride 96.0

Example XV Adipic acid 2.5 Carboxymethyl cellulose acid, 100-200 mesh 2.0 Aluminum carboxymethyl cellulose, 100-200 -mesl1 5, Tryp p hydr ch i 905 Example XVI Aluminum carboxymethyl cellulose, 100-200 Example XVII Calcium polygalacturonate, 40-100 mesh 5.0 Adipic acid 2.5 Threonine hydrochloride 92.5

Example XVIII Aluminum polygalacturonate, 40-100 mesh 20.0 Urea 2.5 Taurine 77.5

One method of making the vehicle of this invention is as follows: The amino acid or mixture of amino acids and the compound which imparts acidity to the vehicle, if required, are mixed until uniform in a helical or other suitable mixer. The mixture is then compressed into slugs one inch in diameter on a tabletting machine. The compressed slugs are ground in a comminuting machine to the desired fineness, the resulting granulation dried for sixteen hours at 50 C. and then mixed with the wicking agent and the material to be incorporated therein, e.g., a therapeutic, contraceptive, or other pharmacologically active ingredient, in a helical or other suitable mixer until uniform. The granulation is compressed to the desired shape and hardness on a tabletting machine.

The wicking agent, as we have designated the material which conducts the vaginal fluid by capillary action or otherwise into the interior of the vehicle, should be water insoluble and capable of absorbing about six percent moisture at 65 percent relative humidity and 70 F. Materials tested and found suitable may be fibrous of nonfibrous and include cellulosic, proteinaceous and synthetic fibers, suchas absorbentcotton, wood cellulose, oxycellulose, silk, rayon, wool andcarboxymethyl cellulose acid. Examples of suitable nonfibrous materials which are water insoluble and which absorb the amount of moisture noted above include the aluminum and calcium salts of al inie acid, pectic acid and polygalacturonic acid.

The wicking agent may be present in the vehicle in different proportions, for example, from about 0.5 percent to about 30 percent, and in different fiber or particle sizes, including on the average of from about 30 mesh to about 325 mesh. In addition, different combinations of wicking agents and mesh sizes may be employed. A combination of carboxymethyl cellulose acid and the alumi num salt of carboxymethyl cellulose acid is particularly suitable because relatively hard vehicles may be made from this combination.

The compounds incorporated in the vehicle to impart acidity should be nontoxic and nonirritating under conditions of use. To prevent gelatinization of vaginal fluid which. inhibits penetration of the fluid into the interior of the vehicle to effect disintegration, an acidic compound may be present in suflicient amounts to provide the vehicle with a pH of from about 3.5 to about 6.5, preferably about 4.0; To determine the pH of the vehicle, two grams of the vehicle are mixed with two grams of distilled water and the pH measured on a Beckman PH meter at-70- F. using a glass-electrode. Acid compounds which have been found satisfactory include boric, succinic, malonic, glutaric, pimelic, tricarballylic, sorbic, maleic, fumaric, citraconic, glycolic, tartaric, adipic, malic, mucic, citric, pyruvic, levulinic, glycine,,phenylacetic, phenylsuccinic, mandelic, cinnamic, serine, sulphanilic, glycerophosphoric, ascorbic and uric. Certain ordinarily classified toxic and irritating acidic compounds maybe used to provide the desired pH, providedthe quantities used are nonirritating and nontoxic under cou- Example XIX p Percent Glycine 90.0 Urea 5.0 Carboxymethyl cellulose acid 2.0 Adipic acid 2.5 Phenyl-p-quinone 0.5

Example XX Glycine 93.5 Carboxymethyl cellulose acid 2.5 Adipic acid 2.0 Nonylphenoxypolyethoxyethanol 2.0

The quantities of each component in the above illustrative examples are preferably present in the following proportions: glycine, from about 65 to about 98.5 percent; carboxymethyl cellulose, from about 0.5 to about 4.0 percent; adipic acid, from about 1 to about 3 percent; and nonylphenoxypolyethoxyethanol, from about 0.15 to about 2 percent. 1

For ease of insertion intravaginally, the vehicle is preferably made in the form of a long, flat tablet with rounded ends and weighing approximately 2 grams. The hardness to which the vehicle may be compressed may vary and we have found that vehicles compressed on a single punch tablet machine produce suitable vehicles when compressed to a hardness of from about 5 to about 12 kilograms measured on the apparatus and in accordance with the method disclosed in U.S. Patent No. 2,041,869. Softer vehicles which have a hardness below 5 kilograms disintegrate with sutiicient speed, but require gentle handling in use and when shipped. Preferably the vehicle is compressed to a hardness of about 7 kilograms when made on a single punch tablet machine.

Laboratory and clinical studies on the vehicle of this invention indicated no untoward reactions, side effects, toxicity or irritation.

It is apparent that variations, substitutions and modifications may be made from the foregoing illustrations without departing from the spirit and scope of this invention.

What is claimed is:

1. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally and will dissolve in water to give an acid pH comprising, in combination, at least one amino acid, the total weight of amino acids present in said vehicle amounting to about 65 to about 99.5 percent and about 0.5 to about 30 percent of a water insoluble wicking agent capable of absorbing about 6 percent moisture at 65 percent relative humidity and 70 F.

2. A pharmaceutical vehicle according to claim 1 containing a spermicidal agent.

3. A pharmaceutical vehicle according to claim 2, in which the spermicidal agent is nonylphenoxypolyethoxyethanol.

4. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally and will dissolve in water to give an acid pH comprising, in combination, at least one amino acid, the total weight of amino acids present in said vehicle amounting to about 65 to about 99.4 percent and about 0.5 to about 30 percent of a water insoluble wicking agent capable of absorbing at least about 6 percent moisture at 65 percent relative humidity and 70 F., and about 0.1 to about 5 percent of a nontoxic, nonirritating acidic compound.

5. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally and will dissolve in water to give an acid pH comprising, in combination, about 65 to about 99.5 percent glutamic acid, and about 0.5 to about 30 percent of a water insoluble wicking agent capable of absorbing about 6 percent moisture at 65 percent relative humidity and 70 F.

6. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally comprising, in combination, about 65 to about 99 percent glutamic acid, about 0.5 to about 30 percent of a water insoluble wicking agent capable of absorbing about 6 percent moisture at 65 percent relative humidity and 70 F., and an acidic compound present in amounts sufiicient to be nontoxic and nonirritating and to provide the vehicle with a pH of from about 3.5 to about 6.5.

7. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally comprising, in combination, about 65 to about 99.5 percent by weight glycine, about 0.5 to about 30 percent of a water insoluble wicking agent capable of absorbing about 6 percent moisture at 65 percent relative humidity and 70 F. I

8. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally comprising, in combination, about 65 to about 99.4 per; cent glycine, about 0.5 to about 30 percent of a water insoluble wicking agent capable of absorbing about 6 percent moisture at 65 percent relative humidity and 70 F., and about 0.1 to about 5 percent of a solid, nontoxic, nonirritating acidic compound, said vehicle having a hardness of about 5 to about 12 kilograms.

9. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally comprising, in combination, about 65 to about 99.4 percent by weight glycine, about 0.5 to about 30 percent of a water insoluble fibrous wicking agent capable of absorbing about 6 percent moisture at 65 percent relative humidity and 70 F., and about 0.1 to about 5 percent of a nontoxic, nonirritating acidic compound.

10. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally comprising, in combination, about 65 to about 99 percent by weight valine, about 0.5 to about 30 percent of a water insoluble, cellulosic wicking agent capable of absorbing about 6 percent moisture at 65 relative humidity and 70 F., and an acidic compound present in amounts sufficie'nt to be nontoxic and nonirritating and to provide the vehicle with an acid pH.

11. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally comprising, in combination, about 65 to about 99.4 percent by weight glycine, about 0.5 to about 30 percent of a water insoluble, proteinaceous wicking agent capable of absorbing about 6 percent moisture at 65 percent relative humidity and 70 F., and an acidic compound present in amounts sufiicient to be nontoxic and nonirritating and to provide the vehicle with an acid pH.

12. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally comprising, in combination, about 65 to about 99 percent by weight glycine, about 0.5 to about 30 percent of a water insoluble wicking agent capable of absorbing about 6 percent moisture at 65 percent relative humidity and 70 F., and being from about 30 to about 325 mesh, and an acidic compound present in amounts sufiicient to be nontoxic and nonirritating and to provide the vehicle with a pH of from about 3.5 to about 6.5.

13. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally comprising, in combination, about 65 to about 99 percent by weight glycine, about 0.5 to about 30 percent of a water insoluble wicking agent capable of absorbing about 6 percent moisture at 65 percent relative humidity and 70 F., and an acidic compound present in amounts sufircient to be nontoxic and nonirritating and to provide the vehicle with a pH of from about 3.5 to about 6.5, said vehicle having a hardness of from. about 5 to about 12 kilograms.

14. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally comprising, in combination, about 63 to about 97 percent glycine, about 0.5 to about 4 percent carboxymethyl celasiaaoa 7 lulose acid, about 1 to about 30 percent aluminum carboxymethyl cellulose and about '1 to about 5 percent adipic acid, said vehicle having a hardness of from about 5' to about 12 kilograms.

15. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally comprising, in combination, about 65 to about 99 percent by Weight glycine, about 0.5 to about 30 percent of a water insoluble wicking agent capable of absorbing about 6 percentmoisture at 65 percent relative humidity and 70 R, an acidic compound present in amounts sufficient to be nontoxic and nonirritating and to provide the vehicle with a pH of from about 3.5 to about 6.5, and a spermidical agent.

16. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally comprising, in combination, about 65 to about 99 percent glycine, about 0.5 to about 30 percent of a water insoluble wicking agent capable of absorbing about 6 percent moisture at 65 percent relative humidity and 70 R, an acidic compound present in amounts sufficient to be nontoxic and nonirritating and to provide the vehicle with an acid pH, and phenyl-p-quinone.

17. A dry, solid, compressed, pharmaceutical vehicle which disintegrates rapidly when introduced intravaginally and will dissolve in waterto give an acid pH comprising,

UNITED STATES PATENTS r 2,219,535 Schmidt Oct. 29, 1940, 2,467,884 Elias Apr. 19, 1949 10 2,484,637 Mattocks Oct. 11, 1949 2,602,042 Abbott July 1, 1952 FOREIGN PATENTS 387,596 Germany Dec. 29, 1923 487,258 Great Britain June 17, 1938 150,013 Australia Feb. 12, 1953 714,870 Germany Dec.. 9, 1941 OTHER REFERENCES I Baker: I. of Hygiene, April 1932, pp. 171-183, esp. pp, 179,480.

Hirschfeld et al.: Arch. of Otolaryngology, December 1946, vol. 44, pp. 686-700, esp. 687.

Zernick: Manuf. Chem.,'Iuly 1939, vol. 10, pp. 241-2, New and Nonoflicial Remedies, 1954, J. B. Lippincott 5 in combination, about to about 97% glycine and about l to about 4% carboxyme'thylcellulose acid and about 2% nonylphenoxypolyethoxyethanol.

References Cited in the file of this patent Co., Philadelphia, pp. XXXIV-XXXV.

il atent No, 2,918,494

vAttesting Oificer UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION December 22, 1959 William C Mende et ,al.1

It is herebfl certified that error appears in the-printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Solumn 6, line' 41 for "abeut 99. 4" read about 99 e Signed and sealed this 7th day of June 19600 {SEAL} Attest:

KARL H. AXLINE ROBERT C. WATSON Commissioner of Patents 

1. A DRY, SOLID, COMPRESSED, PHARMACEUTIAL VEHICLE WHICH DISINTEGRATES RAPIDLY WHEN INTRODUCED INTRAVAGINALLY AND WILL DISSOLVE IN WATER TO GIVE AN ACID PH COMPRISING IN COMBINATION, AT LEAST ONE AMINO ACID, THE TOTAL WEIGHT OF AMINO ACIDS PRESENT IN SAID VEHICLE AMOUNTING TO ABOUT 65 TO ABOUT 99.5 PERCENT AND ABOUT 0.5 TO ABOUT 30 PERCENT OF A WATER-INSOLUBLE WICKING AGENT CAPABLE OF ABSORBING ABOUT 6 PERCENT MOISTURE AT 65 PERCENT RELATIVE HUMIDITY AND 70*F. 